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cta-wave / Test-Content-Generation

Provides all information and scripts how the CTA Wave Test Content is generated
BSD 3-Clause "New" or "Revised" License
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T16, no B-frame #54

Closed Lis-TV closed 2 years ago

Lis-TV commented 2 years ago

The test code sparse Matrix - AVC requires for T16 B-Frames to be present:

Fragment contains multiple chunks (p-frame to p-frame with b-frames)

But when I used ffprobe -i whole_content.mp4 -show_frames there was only I-frames ( pict_type=I ) and P-frames ( pict_type=P )

rbouqueau commented 2 years ago

Where can I find the "sparse Matrix - AVC" reference?

jpiesing commented 2 years ago

https://docs.google.com/spreadsheets/d/1hxbqBdJEEdVIDEkpjZ8f5kvbat_9VGxwFP77AXA_0Ao/edit#gid=0

jpiesing commented 2 years ago

The terminology is copied from the WAVE device playback spec.

rbouqueau commented 2 years ago

I think the important bit here is not the presence of B-Frames or the fragmentation at P-Frames. I think what we are trying to check is multiple ISOBMFF fragments per segment, correct?

If so, I suggest to change the wording of the sparse matrix.

Long story short, supporting "p-frame to p-frame with b-frames" in a generic way would be a permanent hack in the current code.

Adding B-Frames is trivial. Should I add them anyway?

jpiesing commented 2 years ago

The origin of this text is section 10.2.3 of the DPCTF specification.

image

This does explicitly reference B-frames. @haudiobe, I assume you wrote this?

rbouqueau commented 2 years ago

So I've added B-frames with fragment duration based on the number of B-frames in that case.

rbouqueau commented 2 years ago

There was still an issue in the fragment duration computation. Should be solved by 32f04dd34d8f701edd7f4be068d5522e22a5cb9b.

nicholas-fr commented 2 years ago

Resolved in the latest test content, see https://github.com/cta-wave/Test-Content/issues/40#issuecomment-1310031376. I believe this issue can be closed.

gitwjr commented 2 years ago

2022-11-22: Closed based on Nicholas' validation testing of 2022-10-17 test vectors release.